X-ray sources can emit x-rays in all or many directions. It can be important to block x-rays emitted in undesirable directions.
X-ray sources generate a substantial amount of heat. Kinetic energy of electrons hitting a target material on the anode can be converted to heat energy. Also, heat radiated from a filament can heat the anode. An overheated anode target can sublimate and the resulting gas can reduce an internal vacuum of the x-ray tube, thus causing it to fail. It can be important to remove this heat in order to avoid damage to the x-ray source.
Electromagnetic interference from voltage multipliers can interfere with nearby control circuitry. It can be important to prevent or minimize this interference.
Some devices, such as bipolar x-ray sources, include both a negative voltage multiplier and a positive voltage multiplier. It can be important to prevent or minimize electromagnetic interference between these voltage multipliers.
X-ray sources can be heavy due to use of high density material for blocking x-rays and electrical insulating material for isolation of a large voltage differential. Weight reduction can be another important aspect of x-ray sources, particularly portable x-ray sources.